Explore the vast range of titles available.

Renal xenotransplantation has recently made considerable progress in overcoming the barrier to its use in humans. This progress has been made possible owing to the use of preclinical pig-to-primate models. Overall, renal xenotransplantation has long been associated with lower survival rates than that of porcine hearts (mainly due to its life-sustaining nature). However, the use of the latest strains of genetically modified porcine donors, combined with progress in the control of the anti-porcine immune response and coagulation, has now enabled survival of up to 2 years. Although the pig-to-primate combination has long been considered a perfect reflection of the human situation, it has several limitations, particularly in terms of different natural anti-porcine antibodies. This fact, in association with survival prolongation, which is considered a prerequisite, has led some pioneering teams to cross the line of human application. However, use in humans will remain anecdotal, and further progress in renal xenotransplantation will be difficult to achieve without the use of non-human primates, which will remain complementary, particularly with regard to major innovations that have never been tested in humans.

Although the generic drug approval process has a long-term successful track record, concerns remain for approval of narrow therapeutic index generic immunosuppressants, such as tacrolimus, in transplant recipients. Several professional transplant societies and publications have generated skepticism of the generic approval process. Three major areas of concern are that the pharmacokinetic properties of generic products and the innovator (that is, \"brand\") product in healthy volunteers may not reflect those in transplant recipients, bioequivalence between generic and innovator may not ensure bioequivalence between generics, and high-risk patients may have specific bioequivalence concerns. Such concerns have been fueled by anecdotal observations and retrospective and uncontrolled published studies, while well-designed, controlled prospective studies testing the validity of the regulatory bioequivalence testing approach for narrow therapeutic index immunosuppressants in transplant recipients have been lacking. Thus, the present study prospectively assesses bioequivalence between innovator tacrolimus and 2 generics in individuals with a kidney or liver transplant. From December 2013 through October 2014, a prospective, replicate dosing, partially blinded, randomized, 3-treatment, 6-period crossover bioequivalence study was conducted at the University of Cincinnati in individuals with a kidney (n = 35) or liver transplant (n = 36). Abbreviated New Drug Applications (ANDA) data that included manufacturing and healthy individual pharmacokinetic data for all generics were evaluated to select the 2 most disparate generics from innovator, and these were named Generic Hi and Generic Lo. During the 8-week study period, pharmacokinetic studies assessed the bioequivalence of Generic Hi and Generic Lo with the Innovator tacrolimus and with each other. Bioequivalence of the major tacrolimus metabolite was also assessed. All products fell within the US Food and Drug Administration (FDA) average bioequivalence (ABE) acceptance criteria of a 90% confidence interval contained within the confidence limits of 80.00% and 125.00%. Within-subject variability was similar for the area under the curve (AUC) (range 12.11-15.81) and the concentration maximum (Cmax) (range 17.96-24.72) for all products. The within-subject variability was utilized to calculate the scaled average bioequivalence (SCABE) 90% confidence interval. The calculated SCABE 90% confidence interval was 84.65%-118.13% and 80.00%-125.00% for AUC and Cmax, respectively. The more stringent SCABE acceptance criteria were met for all product comparisons for AUC and Cmax in both individuals with a kidney transplant and those with a liver transplant. European Medicines Agency (EMA) acceptance criteria for narrow therapeutic index drugs were also met, with the only exception being in the case of Brand versus Generic Lo, in which the upper limits of the 90% confidence intervals were 111.30% (kidney) and 112.12% (liver). These were only slightly above the upper EMA acceptance criteria limit for an AUC of 111.11%. SCABE criteria were also met for the major tacrolimus metabolite 13-O-desmethyl tacrolimus for AUC, but it failed the EMA criterion. No acute rejections, no differences in renal function in all individuals, and no differences in liver function were observed in individuals with a liver transplant using the Tukey honest significant difference (HSD) test for multiple comparisons. Fifty-two percent and 65% of all individuals with a kidney or liver transplant, respectively, reported an adverse event. The Exact McNemar test for paired categorical data with adjustments for multiple comparisons was used to compare adverse event rates among the products. No statistically significant differences among any pairs of products were found for any adverse event code or for adverse events overall. Limitations of this study include that the observations were made under strictly controlled conditions that did not allow for the impact of nonadherence or feeding on the possible pharmacokinetic differences. Generic Hi and Lo were selected based upon bioequivalence data in healthy volunteers because no pharmacokinetic data in recipients were available for all products. The safety data should be interpreted in light of the small number of participants and the short observation periods. Lastly, only the 1 mg tacrolimus strength was utilized in this study. Using an innovative, controlled bioequivalence study design, we observed equivalence between tacrolimus innovator and 2 generic products as well as between 2 generic products in individuals after kidney or liver transplantation following current FDA bioequivalence metrics. These results support the position that bioequivalence for the narrow therapeutic index drug tacrolimus translates from healthy volunteers to individuals receiving a kidney or liver transplant and provides evidence that generic products that are bioequivalent with the innovator product are also bioequivalent to each other. ClinicalTrials.gov NCT01889758.

Background Low physical activity and reduced physical functioning are common after renal transplantation, resulting in a reduced quality of life. Another common post-transplantation complication is poor cardio-metabolic health, which plays a main role in long-term outcomes in renal transplant recipients (RTR). It is increasingly recognized that weight gain in the first year after transplantation, especially an increase in fat mass, is a highly common contributor to cardio-metabolic risk. The aim of this study is to compare the outcomes of usual care to the effects of exercise alone, and exercise combined with dietary counseling, on physical functioning, quality of life and post-transplantation weight gain in RTR. Methods The Active Care after Transplantation study is a multicenter randomized controlled trial with three arms in which RTR from 3 Dutch hospitals are randomized within the first year after transplantation to usual care, to exercise intervention (3 months supervised exercise 2 times per week followed by 12 months active follow-up), or to an exercise + diet intervention, consisting of the exercise training with additional dietary counseling (12 sessions over 15 months by a renal dietician). In total, 219 participants (73 per group) will be recruited. The primary outcome is the subdomain physical functioning of quality of life, (SF-36 PF). Secondary outcomes include other evaluations of quality of life (SF-36, KDQOL-SF, EQ-5D), objective measures of physical functioning (aerobic capacity and muscle strength), level of physical activity, gain in adiposity (body fat percentage by bio-electrical impedance assessment, BMI, waist circumference), and cardiometabolic risk factors (blood pressure, lipids, glucose metabolism). Furthermore, data on renal function, medical history, medication, psychological factors (motivation, kinesiophobia, coping style), nutrition knowledge, nutrition intake, nutrition status, fatigue, work participation, process evaluation and cost-effectiveness are collected. Discussion Evidence on the effectiveness of an exercise intervention, or an exercise + diet intervention on physical functioning, weight gain and cardiometabolic health in RTR is currently lacking. The outcomes of the present study may help to guide future evidence-based lifestyle care after renal transplantation. Trial registration Number: NCT01047410 .

Background Non-adherence to immunosuppressive therapy is a prevalent risk factor for poor clinical and after kidney transplantation (KT), and has contributed to the lack of improvement in long-term graft survival over the past decade. Understanding the multilevel correlates and risk factors of non-adherence is crucial to determine the optimal level for planning interventions, namely at the patient, health care provider, KT centre, and health care system level. Brazil, having the largest public transplantation program in the world and with regional differences regarding access to health services and service implementation, is in a unique position to study this multilevel approach. Therefore, the Adhere Brazil Study (ADHERE BRAZIL) was designed to assess the prevalence and variability of non-adherence to immunosuppressants and to health behaviours among adult KT recipients in Brazil, and to assess the multilevel correlates of non-adherence to immunosuppressive medication. We describe the rationale, design, and methodology of the ADHERE BRAZIL study. Methods/Design This is an observational, cross-sectional, multicentre study that includes 20 Brazilian KT centres. A stratified sampling approach is used, based on strata, with the following characteristics considered: geographical region and transplant activity (number of KTs per year). A random sample of patients (proportional to the size of the centre within each stratum) is selected from each centre. The prevalence of different health behaviours is assessed through self-report. The assessment of multilevel correlates of non-adherence is guided by the ecological model that considers factors at the level of the patient, health-care professional, and transplant centre, using established instruments or instruments developed for this study. Data will be collected over an 18-month period, with information obtained during the regular follow-up visits to the transplant outpatient clinic and directly entered into the Research Electronic Data Capture (RedCap) system. Data entry is performed by a trained professional who is part of the transplant team. The data collection began in December 2015. Discussion This multicentre study is the first to evaluate multilevel correlates of non-adherence in KT patients and will provide a reliable estimate of non-adherence in Brazilian KT patients. Trial registration ClinicalTrials.gov on 10/10/2013, NCT02066935 .

Background Dosage quantities of tacrolimus (TAC) vary according to cytochrome P450 3A5 (CYP3A5) genotype. Genotyping is expected to optimize the response to TAC response and to minimize adverse effects. In Thailand, kidney transplantation is reimbursable with the same diagnosis-related group payment regardless of patient’s CYP3A5 genotype. Objective This study aimed to determine the costs of TAC administration, therapeutic drug monitoring (TDM), and hospitalization for kidney transplantation across CYP3A5*1/*1, *1/*3, and *3/*3 genotypes. Setting A single transplant center in a university hospital. Method This is an observational study that collected data from patients pooled from both arms of a randomized controlled trial that tested initial doses of TAC. Main outcome measure TAC and TDM cost and hospitalization cost for transplantation were compared between genotypes. Results The CYP3A5*1/*1 patients had the highest median combined TAC–TDM cost and hospitalization cost ( $1062 and $ 9097), followed by CYP3A5*1/*3 ( $859 and $ 6467) and CYP3A5*3/*3 patients ( $761 and $ 5604). The CYP3A5*1/*1 patients had a higher hospitalization cost by$2787 over the CYP3A5*1/*3 patients, despite marginal significance. The CYP3A5*1/*1 patients had a significantly higher cost of TAC plus TDM (by $ 309) and hospitalization cost (by $3275) than the CYP3A5*3/*3 patients. Both study costs were significantly higher in patients with delayed graft functioning than in patients with instant or slow graft functioning. Conclusion The benefits of genotype detection in patients with CYP3A5*1/*1 should be considered for a higher reimbursement rate because of the substantial differences in total hospitalization cost for kidney transplantation among patients with different CYP3A5 genotypes.

Background Conversion from calcineurin inhibitor (CNI) therapy to a mammalian target of rapamycin (mTOR) inhibitor following kidney transplantation may help to preserve graft function. Data are sparse, however, concerning the impact of conversion on posttransplant diabetes mellitus (PTDM) or the progression of pre-existing diabetes. Methods PTDM and other diabetes-related parameters were assessed post hoc in two large open-label multicenter trials. Kidney transplant recipients were randomized (i) at month 4.5 to switch to everolimus or remain on a standard cyclosporine (CsA)-based regimen (ZEUS, n  = 300), or (ii) at month 3 to switch to everolimus, remain on standard CNI therapy or convert to everolimus with reduced-exposure CsA (HERAKLES, n  = 497). Results There were no significant differences in the incidence of PTDM between treatment groups (log rank p  = 0.97 [ZEUS], p  = 0.90 [HERAKLES]). The mean change in random blood glucose from randomization to month 12 was also similar between treatment groups in both trials for patients with or without PTDM, and with or without pre-existing diabetes. The change in eGFR from randomization to month 12 showed a benefit for everolimus versus comparator groups in all subpopulations, but only reached significance in larger subgroups (no PTDM or no pre-existing diabetes). Conclusions Within the restrictions of this post hoc analysis, including non-standardized diagnostic criteria and limited glycemia laboratory parameters, these data do not indicate any difference in the incidence or severity of PTDM with early conversion from a CsA-based regimen to everolimus, or in the progression of pre-existing diabetes. Trial registration clinicaltrials.gov , NCT00154310 (registered September 2005) and NCT00514514 (registered August 2007); EudraCT ( 2006-007021-32 and 2004-004346-40 ).

Background Effective interventions to improve immunosuppressive medication adherence among adolescent and young adult kidney transplant recipients are desperately needed. This paper describes the aims, design, and methods of the Teen Adherence in Kidney transplant, Effectiveness of Intervention Trial (TAKE-IT) study. Design and methods TAKE-IT is a multicentre, prospective, open-label, parallel arm randomized controlled trial that aims to determine the effectiveness of a clinic-based intervention, including educational, organizational, and behavioural components, in improving immunosuppressive medication adherence among adolescent and young adult kidney transplant recipients. Individuals between 11 and 24 years of age who are at least 3 months post-transplant and followed in one of the eight participating pediatric kidney transplant programs, or their affiliated adult transplant programs are eligible to participate. All participating centers are tertiary care pediatric hospitals in Canada or the United States. Adherence is monitored using an electronic multi-dose pillbox for all participants during a 3-month run-in period, followed by a 12-month intervention interval. The primary outcome is ‘taking adherence’, defined as the proportion of prescribed doses of immunosuppressive medications that were taken, as measured using electronic monitoring. All participants meet with the study ‘Coach’ at 3 month intervals. The intervention, administered by trained lay personnel, targets common adherence barriers. In addition to forming an Adherence Support Team, intervention participants identify personal barriers to adherence and use Action-focused problem-solving to address them, have their electronic adherence data fed back to them, and have the option to receive email, text message, or visual cue dose reminders. Participants in the control group meet with the coach but do not receive the other components of the intervention. The study aims to have 75 participants in each group complete the study. Discussion Since recruitment began in Feb. 2012, 198 adolescents have been approached to participate, of whom 130 have completed a baseline visit. As of March 31, 2014, 125 had been randomized, and 86, 68, 61, and 50 participants had completed 6-month, 9-month, 12-month, and 15-month visits respectively. Trial registration Clinicaltrials.gov registration NCT01356277 (May 17, 2011).

Background Cardiovascular complications are common in kidney transplant patients and calcification propensity of blood, measured as T 50 , is associated with cardiovascular outcomes. Paricalcitol supplementation affects calcium/phosphate homeostasis and may affect calcification propensity. To assess this hypothesis we measured T 50 in kidney transplant recipients participating in a randomized study comparing paricalcitol versus no treatment during the first year after kidney transplantation. Methods Stored serum samples from 76 kidney transplant recipients (paricalcitol n  = 37, no treatment n  = 39) were analyzed. Analyses were performed at inclusion (8 weeks after transplantation) and repeated one year after transplantation. Results There were no statistically significant differences in T 50 between the paricalcitol and placebo groups, neither at baseline ( p  = 0.56) nor at 1 year ( p  = 0.61). Also, there were no significant changes in T 50 over time in either group or when pooling all data ( p  <  0.20). In multivariate regression analysis, out of 16 potentially relevant covariates, comprising clinical and biochemical parameters, only plasma PTH and T 50 at baseline were significantly correlated to T 50 after one year. ( p  <  0.03 and p  < 0.01, respectively). Conclusions Calcium propensity measured as T 50 score remained unchanged with paricalcitol treatment in kidney transplant recipients, and was not changed over time during the study period of one year. Trial registration ClinicalTrials.gov, NCT01694160 , registered 23 September 2012.

Background Conversion from calcineurin inhibitor (CNI) therapy to everolimus within 6 months after kidney transplantation improves long-term graft function but can increase the risk of mild biopsy-proven acute cellular rejection (BPAR). We performed a post-hoc analysis of histological data from a randomized trial in order to further analyze histologic information obtained from indication and protocol biopsies up to 5 years after transplantation. Methods Biopsy samples obtained up to 5 years post-transplant were analyzed from the randomized ZEUS study, in which kidney transplant patients were randomized at month 4.5 to switch to everolimus ( n  = 154) or remain on cyclosporine (CsA)-based immunosuppression ( n  = 146). All patients received mycophenolate and steroids. Results At least one investigator-initiated biopsy was undertaken in 53 patients in each group between randomization and year 5, with a mean (SD) of 2.6 (1.7) and 2.2 (1.4) biopsies per patient in the everolimus and CsA groups, respectively. In the everolimus and CsA groups, investigator-initiated biopsies showed (i) BPAR in 12.3 and 7.5% ( p  = 0.182) of patients, respectively, with episodes graded mild in 22/24 and 18/20 cases (ii) CsA toxicity lesions in 4.5 and 10.3% of patients ( p  = 0.076) (iii) antibody-mediated rejection in 0.6 and 2.7% of patients ( p  = 0.204), respectively. Conclusions This analysis of histological findings in the ZEUS study to 5 years after kidney transplantation shows no increase in antibody-mediated rejection under everolimus-based therapy with a lower rate of CNI-related toxicity compared to a conventional CsA-based regimen, and confirms the preponderance of mild BPAR seen in the main study after the early switch to CsA-free everolimus therapy. Trial registration ClinicalTrials.gov NCT00154310 . Date of registration: September 12, 2005.

Background Weight gain and obesity are common after kidney transplantation, particularly during the first year. Obesity is a risk factor for the development of new-onset diabetes after transplantation, and is associated with reduced graft survival. There is a lack of evidence for effective interventions to prevent weight gain after kidney transplantation. Methods/Design The effect of INTE nsive N utrition interventions on weight gain after kidney T ransplantation (INTENT) trial is a single-blind (outcomes assessor), randomised controlled trial to assess the effect of intensive nutrition interventions, including exercise advice, on weight gain and metabolic parameters in the first year after transplantation. Participants will be randomised during the first post-transplant month to either standard care (four visits with a renal dietitian over twelve months) or intensive nutrition intervention (eight visits with a renal dietitian over the first six months, four visits over the second six months, and three visits over the first six months with an exercise physiologist). In the intensive intervention group, nutrition counselling will be provided using motivational interviewing techniques to encourage quality engagement. Collaborative goal setting will be used to develop personalised nutrition care plans. Individualised advice regarding physical activity will be provided by an exercise physiologist. The primary outcome of the study is weight at six months after transplant, adjusted for baseline (one month post-transplant) weight, obesity and gender. Secondary outcomes will include changes in weight and other anthropometric measures over 12 months, body composition (in vivo neutron activation analysis, total body potassium, dual-energy X-ray absorptiometry, and bioelectrical impedance), biochemistry (fasting glucose, lipids, haemoglobin A1c and insulin), dietary intake and nutritional status, quality of life, and physical function. Discussion There are currently few randomised clinical trials of nutrition interventions after kidney transplantation. The INTENT trial will thus provide important data on the effect of intensive nutrition interventions on weight gain after transplant and the associated metabolic consequences. Additionally, by assessing changes in glucose metabolism, the study will also provide data on the feasibility of undertaking larger multi-centre trials of nutrition interventions to reduce the incidence or severity of diabetes after transplantation. Trial registration Australian New Zealand Clinical Trials Registry Number: ACTRN12614000155695